Prosthetic revision knee system

Abstract

The present invention provides a femoral component, and a method for surgical implantation of a femoral prosthesis, comprised of a revision knee implant and corresponding cutting block system. In particular, the revision knee implant, comprised of a femoral component having incremental markings thereon and a femoral stem, and corresponding cutting block system having corresponding incremental markings thereon, enables a surgeon maximally to position the cutting block adjacent as much area as possible of a distal femur of a patient and to infinitely position the femoral component in the exact position indicated by the cutting block.

Description

BACKGROUND OF THE INVENTION[0001]1. Field of the Invention[0002]The present invention relates to revision knee implants and surgical orthopedic cutting instruments, and more particularly relates to an improved revision knee femoral prosthesis and corresponding improved cutting block apparatus for shaping a distal femur of a patient prior to implantation of the femoral prosthesis.[0003]2. Description of Related Art[0004]In patients who require a revision knee system implant, there typically is much bone loss, and thus a lack of normal bony reference points or landmarks for properly aligning the implant. In these cases, surgeons use the intramedullary canal of the femur as a landmark for positioning the prosthesis. If the femoral stem of the implant is not properly aligned with respect to the intramedullary canal in the anterior-posterior direction, there will be a gap between the natural femur and the femoral component at the anterior or posterior end.[0005]A conventional knee prosth...

AI Technical Summary

Problems solved by technology

In patients who require a revision knee system implant, there typically is much bone loss, and thus a lack of normal bony reference points or landmarks for properly aligning the implant.

One of the problems encountered by the surgeon is the proper orientation of the cuts so that the prosthesis will fit the femur with the correct orientation.

For example, the anterior-posterior position of the femoral stem usually is not adjustable or only adjustable in limited increments, in both cases resulting in poor alignment of the femoral prosthesis with respect to the intramedullary canal of the femur or an unbalanced flexion gap, either of which can lead to deterioration of the implant.

If the bolt loosens, it can migrate into the knee joint, resulting in injury to the surrounding tissue and damage to or interference with the prosthesis.

Additionally, such nut and bolt systems can introduce particulate matter into the knee joint which can cause infection or lead to inflammatory immune responses.

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